Rebuild target 'Target 1'
compiling main.c...
compiling system_stm32f4xx.c...
assembling startup_stm32f40xx.s...
linking...
c:/armgnu/4.9 2014q4/bin/../lib/gcc/arm-none-eabi/4.9.3/../../../../arm-none-eabi/lib/armv7e-m\libc.a(lib_a-exit.o): In function `exit':
exit.c:(.text.exit+0x16): undefined reference to `_exit'
collect2.exe: error: ld returned 1 exit status
".\blinky.elf" - 1 Error(s), 0 Warning(s).
Target not created.
Build Time Elapsed:  00:00:00